1. Field of the Invention
The present invention relates to a magneto-rheological elastomer composition, more specifically, a magneto-rheological elastomer composition that greatly changes its storage modulus upon application of magnetism, a method for producing the same, and a vibration absorbing device including the same.
2. Description of Related Art
A fluid that changes its rheological property upon application of a magnetic field is called a magneto-rheological fluid (MR fluid), and known as a non-colloidal suspension in which magnetically active particles such as fine magnetic powder are dispersed uniformly in a liquid. The MR fluid can be used not only for impact absorption, power transmission and attitude control, but also for clutches, dampers and shock absorbers of vehicles, damping support devices for various structures, muscle parts of assembly robots, liquid flow rate control valves, various acoustic systems, and medical and welfare robotic hands and care hands. However, since the MR fluid has poor handleability, MR elastomers with high handleability have been proposed recently.
Patent Document 1 proposes dispersing a magnetic filler such as permalloy (Fe—Ni alloy) in a viscoelastic resin material and rotationally molding it to obtain a magnetic field responsive composition. Patent Document 2 proposes dispersing a magnetic filler in a viscoelastic resin material and curing it during application of a magnetic field. Patent Document 3 proposes orienting magnetic particles in a resin material, and Patent Document 4 proposes not orienting magnetic particles in a resin material.